Bridges for Service Life Beyond 100 Years: Service Limit State Design (2014)

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292 A p p e n d i x B SHRP 2 R19B Survey of Bridge Owners

293 Questionnaire #1 Summary of Experience with Service Issues Your Name and Title: Your Phone Number and Email Address: Please address the following questions as they relate to summarizing your experience by material type, structure type and subsystem, component and element type. The following are possible examples of these various features: • Material Type: steel, plain concrete, reinforced concrete, prestressed concrete, etc. • Structure Type: I girder bridge, box girder bridge, segmental bridges, truss, cable stayed, etc. • Subsystems: superstructure, substructure, foundations, drainage systems, etc. • Component: bearing, expansion joint Please make as many copies of the appropriate questions as needed for the structure types, materials, subsystems or components for which you are responding. General Questions 1. What are the five or ten most costly maintenance/durability items in your structural maintenance budget? 2. Does your agency utilize deterioration models other than those in Pontis? If so, What and why? 3. The current LRFD service limit states include limits on: • live load deflection of bridges, • cracking of reinforced-concrete components, • tensile stresses of prestressed-concrete components, • compressive stresses of prestressed concrete components, • permanent deformations of compact steel components, • slip of slip-critical friction bolted connections, and • settlement of shallow and deep foundations. In your experience, are these service limit states adequate for your needs or are further safeguards required? If more are required, what should they guard against for what types of members, systems or details? Specific Questions for Structure Type, Material Subsystem or Component Structure Type: Material: Subsystem or Component if Appropriate: 4. What have you seen as the important service and durability issues (not strength) and bridge age affects that impact the serviceability of bridge components? 5. Have you seen issues resulting in reduced serviceability (or a trend in that direction) that could have been avoided if the design specifications had additional service (not strength) design requirements? If so, what? 6. What type of foundation/wall settlement or other movements have resulted in maintenance issues or reduced serviceability? 7. Do you make Quantitative/Qualitative condition assessments beyond what is in Pontis? If so, has this data provided insight into serviceability requirements? 8. Have you seen a direct correlation between deterioration and reduced serviceability (not nuisance maintenance)? If so, in what types of structures/components? Have you been able to quantify the rate of reduced serviceability or service life? 9. Are there other questions we should have asked to gain more insight into your experience with service limit states? If so, what are they and what would your responses have been?

294 Questionnaire #2 Geotechnical Service Issues ForM For BrIdGE MovEMEnTS and oBSErvEd dISTrESS 1. Preparer Information (fill one form per structure) Prepared by/Title/Agency (Dept.) Phone/E-mail 2. Bridge Information State/County/Town Route No./Structure No. Year built Crossing (over/under) No. of spans Type of spans (simple, continuous, cantilever, etc.) Type of superstructure (steel, concrete, girder, slab, box beam, etc.) Type of abutments (integral, spill-through, full height, perched, stub, etc.) Pier foundation type (spread footings, driven piles, drilled shafts, etc.) Approach fill or wall type (Fill with side slope, MSE wall, etc.) Approach height As-built drawings available? Geotechnical report available? Boring logs available? Were repairs performed? Maintenance records available? Any instrumentation data available? Any photos of bridge damage and/or repairs available? 3. Construction Sequence: Fill in 1, 2 and 3 based on sequence of construction of following elements Substructure _________________ Superstructure _________________ Approach fill/wall _________________ 4. Geologic Information: Describe generalized geologic strata including soil types, water table location, Standard Penetration Test (SPT) N-values, consolidation parameters, etc. If geotechnical report including boring logs is provided, refer to the report and no further information is necessary.

295 5. Bridge Movements (horizontal movements are movements in longitudinal direction of bridge) Vertical Movements Abutments Piers Horizontal Movements Abutments Piers Estimated Estimated Observed Observed Note: If varied movement was observed at different support elements, provide additional information on a separate page as appropriate. 6. Effect of Movements on Bridge Structure: Indicate if distress types were tolerable or not based on the following definition: “Movement is NOT tolerable if damage requires costly maintenance and/or repairs AND a more expensive construction to avoid this would have been preferable.” (Use additional pages if necessary to provide detailed information on any distress type) # distress Type Tolerable? (Yes/no), description 1 Damage to abutments: cracking and spalling of abutments, abutment footings, abutment pile caps, or abutment slope protection; also included in this category are the opening, closing or damage to abutment joints, the separation of the wingwall from abutment, and the rupturing or exposure of abutment foundations. 2 Damage to piers: cracking and spalling of piers, pier footing, pier pile caps, or struts of diaphragms between pier columns. 3 Vertical displacement: raising or lowering of the superstructure above or below planned grade or a sag or heave in the deck; structures requiring shimming or jacking as well as truss structures with increase camber are also included. 4 Horizontal displacement: structures with a misalignment of bearings and superstructure, or beams jammed against abutments; bridges where superstructure extended beyond the abutment, where beams required cutting, or where there was horizontal movement of the floor system. 5 Distress in superstructure: cracks or other evidence of excessive stress in beams, girders, struts, and diaphragms as well as cracking and spalling or the deck; shearing of anchor bolts; opening, closing or damage of deck joints and cases where the cutting or relief joints were required. 6 Damage to railings, curbs, sidewalks or parapets: cracking, deformation, or misalignment of railing, curb, sidewalks, or parapets; jammed curbs and crushed concrete and open, closed or damaged portions of these elements. 7 Damage to bearings: tilting or jamming or rockers as well as cases where rockers have pulled off bearing, or where movement results in an improper fit between bearing shoes and rockers requiring re-positioning; deformed neoprene/elastomeric bearing pads, sheared anchor bolts in the bearing shoes, damage to expansion devices, and cracking of concrete at the bearings. 8 Poor riding quality: reported noticeable driver discomfort. 9 Not given or corrected during construction: those cases where any mention of structural effects was omitted or where foundation movement was corrected prior to construction of the superstructure. 10 None: no damage or repairs. 11 Other: other observed distress types not included in above categories.

296 agency’s Tolerable Movement Criteria for new Bridge Structures 1. Article C10.5.5.2 of AASHTO (2007) allows angular distortion of 0.004 for multiple (continuous) spans and 0.008 for single-span bridges. Does your agency follow these criteria? (Yes/No) _____. [Note: Angular distortion is defined as DS/L where DS is the differential settlement between two support elements and L is the distance between support elements (i.e., span length). Example: limiting angular distortion of 0.004 permits a differential settlement of 4.8-inches over a 100-ft span length.] If answer to above question is “No,” please provide following information. If criteria vary by span length, number of spans and/or structure type (steel vs. concrete, girder vs. box beam, etc.) provide additional information as appropriate: Permissible total vertical movement (settlement), S, at any given support element Permissible differential vertical movement (settlement), DS, within a given span Permissible angular distortion, DS/L (where L is span length) Permissible horizontal movement, H (in longitudinal direction of the bridge) Additional Information: 2. Does the agency have criteria for permissible horizontal movement (in longitudinal direction of the bridge)? (Yes/No) _______. If answer to above question is “Yes,” please provide following information. If criteria vary by span length, number of spans and/or structure type (steel vs. concrete, girder vs. box beam, etc.) provide additional information as appropriate: Permissible horizontal movement, H (in longitudinal direction of the bridge) Additional Information:

297 response to Questionnaire 1 on Superstructure Issues Question 1: What are the five or ten most costly maintenance/ durability items in your structural maintenance budget? The most costly maintenance/durability items within the structural maintenance budget as reported in the survey responses are: • Expansion joints and steel coating systems (13 each); • Concrete decks (cracking, repair, and sealing for cracking) (8); • Deck overlays and bearings (7 each); • Concrete and steel repair or replacement (5 each); • Abutment maintenance (3); • Timber components, movable bridges, approach slabs, rail- ings and curbs, reinforcement, fatigue, built-up steel corro- sion, and scour (2 each); and • Weld cracking, slope maintenance, anchor cables, deck drains, concrete coatings, header joints, and concrete spalling (1 each). Question 2: does your agency utilize deterioration models other than those in Pontis? If so, what and why? Fifteen survey responses were received and indicate that the following are used to estimate deterioration: • Utilize Pontis only (8); • Use a DOT created program (5); and • Use experience or use no deterioration models (1 each). The responses indicate that most agencies use models to esti- mate deterioration. Those that do not use either Pontis or a DOT specific program use engineering judgment or do not attempt to estimate deterioration. Some programs consist of computer software created using data combined with experi- ence in estimating remaining service life. Other programs combine condition assessments completed for NBI inspec- tions and curves developed based on the structure type. Several of the DOT programs use different elements in the deteriora- tion models than are used in Pontis. Question 3: In your experience, are the current SLS adequate for your needs or are further safeguard required? If more are required, what should they guard against for what types of members, systems or details? The responses to this question were as follows: • Adequate but a need for additional requirements (9); • Adequate (6); and • Some of the current SLS are over conservative (2). Most respondents felt that the current SLS are adequate as cur- rently specified. Two responses felt that at least one limit state was over conservative, with one believing the L/800 limit for live load deflections is over conservative while the other related to whether AASHTO LRFD 5.7.3.4-Control of Cracking by Distri- bution of Reinforcement is over conservative. The responses suggested adding serviceability limit states with regards to: • foundation settlement of approach pavement; • relative movement between adjacent girders and determina- tion the factored out-of-plane resistance for this condition; • consider steel corrosion/section loss based on type of steel coating and a corrosion model and then rechecking stresses based on reduced section; • consider local deflections or incompatible deformations at component interfaces; • requirements for stress and cracking of reinforced concrete flexural members (current method of designing for strength and then checking crack control reinforcement is not ade- quate and members crack resulting in reduced service life, this agency no longer uses reinforced concrete bridge beams); • serviceability of connections; and • SLS for expansion joints and bearings. Question 4: What have you seen as important service and durability issues (not strength) and bridge age affects that impact the serviceability of bridge components? The fourteen responses to the above question included: • Deck cracking (6); • Corrosion of steel, steel coating systems, and leaking expan- sion joints (5 each); • Fatigue (4); • Bearing failure, chloride penetration, and deterioration of beam ends (3 each); • Preparation for steel painting, ADT combined with salt (2 each); and • Slope failure, end bent movement, deck drainage, deck mem- brane durability, bond and splice lengths, deterioration of non-composite bridge decks, exodermic bridge decks, bent cracking, concrete mix design, foundation movement, con- crete deterioration, deflections and vibrations, adequate detailing, and the requirements for appropriate cover ver- sus the requirements for crack control steel (1 each). The results are combined for all bridge types and components. The most common issue mentioned was deck cracking closely followed by corrosion of steel in reinforced concrete and steel superstructures and painting of steel. Often times both were mentioned as “proper painting of the steel girders will slow down the corrosion process.” In addition, leaking expansion

298 joints was a common response, which may be related to many of the other issues mentioned. As would be expected, the chlo- ride penetration and “ADT and salt” categories were focused in the northern part of the country where winter weather con- ditions require the use of salt for traffic safety. Question 5: Have you seen issues resulting in reduced ser- viceability (or a trend in that direction) that could have been avoided if the design specification had additional ser- vice (not strength) design requirements? If so, what? The thirteen responses to the above question included: • Reduced serviceability could not have been avoided with additional service requirements (7) • Additional requirements that would have helped avoid reduced serviceability were as follows: 44 Crack control requirements for concrete decks and pro- visions to limit corrosion of deck reinforcement; 44 Requirements to check for expansion caused by thermal loading (this is already included in the design specifica- tion for ULS and SLS); 44 Provisions for use of proprietary deck systems; 44 Specifications for proper fill materials to prevent slope failures; and 44 Cracking of cantilevered portions of bents—for sec- tions with shear span to depth ratios of approximately 1.5, limit service load stresses in longitudinal reinforce- ment are limited to 30 ksi at column face (up to 36 ksi at column center) for moderate exposures and up to 24 ksi and 30 ksi at the column face and center, respec- tively, for severe exposures. Most respondents believe that no, new additional serviceabil- ity requirements are necessary. Those that believed reduced serviceability could have been avoided suggested new service- ability requirements for the bridge deck and foundation and substructure. Others were not sure whether issues resulting in reduced serviceability could have been avoided had there been additional service requirements. Question 6: What type of foundation/wall settlement or other movements have resulted in maintenance issues or reduced serviceability? Twelve respondents indicated different types of foundation or wall settlement and movement that have resulted in reduced serviceability or maintenance include: • No foundation problems (3); • Scour at spread footings and retaining structures, settle- ment or movement of approach slabs, MSE and retaining walls, and wingwalls (3 each); • Poor soil, movement of piles, and movement of abutments (2 each); and • Movement of end bents and rotation of spread footings (1 each). Foundation problems varied greatly, with some responses indi- cating no foundation problems while others had many prob- lems. One response said that they had no foundation problems but indicated that they had previously had some but these were eliminated using rules of thumb or by setting guidelines that require all foundations to be at the same level. They also said that the service issues with foundations were caused by con- struction issues. Those that noted movement of MSE or retain- ing walls as causing reduced serviceability noted that in one case the movement was caused by thermal loading and the other was a result of the bridge being supported by piling while the retaining walls were not. Question 7: do you make Quantitative/Qualitative condi- tion assessments beyond what is in Pontis? If so, has this data provided insight into serviceability requirements? Thirteen responses were received indicating whether addi- tional assessments are completed and if they provide insight into serviceability requirements: • No additional quantitative or qualitative assessments (7); • No additional quantitative but do complete additional qualitative assessments (3); and • Complete both additional quantitative and qualitative assessments (3). The first agency that completes both additional assessments used various methods, such as, bridge deck condition sur- veys, measurement of chloride penetration depth, and ultra- sonic testing to measure corrosion combined with engineering judgment to determine priority for replacement or rehabili- tation. The second agency completing additional assessments uses a condition scale for each bridge component and provides relevant notes and figures that portray the overall condition and what deficiencies exist. This agency also noted that the use of additional inspections show the same conditions over and over in their bridge inventory but did not state what conditions these were, suggesting that there is a need for enhanced service- ability requirements. The third agency completing additional quantitative/qualitative assessments while providing insight into the deterioration of the structure have not been used with regard to additional serviceability requirements. Question 8: a. Have you seen a direct correlation between deterioration and reduced serviceability (not nuisance main- tenance)? If so, in what types of structures or components?

299 b. Have you been able to quantify the rate of reduced service- ability or service life? Thirteen responses were received in regards to Question 8a. The responses included: • Expansion joints and associated deterioration of beam ends and substructure units (11); • Bridge decks (5); • No correlation (2); and • Joints and timber piles (1 each). The results suggest that many of the responding agencies have determined that there is a correlation between deterioration in different bridge components and reduced serviceability. The most common response was corrosion or section loss of a steel girder/beam resulting in higher stresses under service loads. Additionally, correlations between deterioration and reduced serviceability were noted for all components of a bridge, from the foundation to the superstructure and deck. The results noted that there was a reduction in service life for bridge decks and load carrying capacity for girders. The fourteen responses were received for Question 8b regarding the quantification of reduced serviceability are: • No (12); and • Yes (2). The second part of question 8 was whether the different agen- cies had tried to quantify the rate of reduced serviceability. The overwhelming response was No, but two indicated that they had, or were trying to, quantify the reduction in serviceability. One agency used engineering judgment to quantify the reduc- tion in serviceability and service life of bridge decks while the other was trying to determine a method to quantify the rate of deterioration for deck systems which incorporated a sealer and also to quantify the difference in deterioration between steel girders with and without a protective coating. Question 9: are there other questions we should have asked to gain more insight into your experience with SLS? If so, what are they and what would your responses have been? Seven agencies answered Question 9 regarding other questions that should have been asked. Their responses are as follows: • No (4) and • Yes (3). Approximately half of the agencies that provided a response to the question (i.e., 3 agencies) had additional questions that could have been asked or comments/suggestions. The follow- ing are their suggestions: • Provide SLS for permit trucks similar to the Strength II limit state. • Load test all bridge type/material combinations except for steel. Additional questions regarding the following items could have been asked: • What alternative design loads (alternatives to HL-93) are being used to check limit states by other agencies? (This was covered by NCHRP 12-83) • What types of corrosion protection systems are required? • What types of exposures and associated environmental distresses have you observed? • How have locked in connection forces due to permanent deformations affected serviceability? • What effects on bearings and joints have you seen due to creep, shrinkage, and uniform and gradient temperature changes? and • How do live load deformations affect connections? responses to Questionnaire #2 on Geotechnical Issues Only three respondents provided significant information in response to this part of the survey. All respondents framed their response in terms of experience with specific bridges. The rel- evant information is summarized in the following table. The first four bridges are from the same state. They indicated that they had observed distress in almost all cases where an integral abutment and an unisolated MSE mass were used and foun- dation movement occurred. Four responses were obtained to Question 6 regarding effects of movement on the structure. Three of the four are from the agencies that provided responses to Questions 1 through 5 of this questionnaire. A majority of responses believe that the different types of movement listed are not tolerable while some believe that movement is tolerable until it starts affecting other structural components. The effects of movement resulted in varying degrees of damage or distress to the structure. The first response indicated that movement and damage caused by movement is not tolerable according to the defini- tion provided. While movement and associated damage is not tolerated, they believe that poor riding quality is tolerable. The second response provided repair methods for the differ- ent types of movement listed. These include repairing vertical settlement due to beam deterioration by jacking the beam and repairing the section loss. Poor riding quality was improved by mudjacking the approach slabs. Damage to bearings is repaired by either replacing bearings with elastomeric bearing pads or resetting rocker bearings. The third response indicated that movement occurred caus- ing a hinge to form over the pier resulting in the loss of bearing

300 Table B.1. Bridge Characteristics, Geological Information, and Movements Question 1: Preparer Assistant Geotechnical Engineer (State A) DOT (State B) DOT (State C) Question 2: Bridge Characteristics Year built 1999 1998 2007 2002 1963 1999 No. of spans 5 5 5 3 3 6 Type of superstructure (steel, concrete, girder, slab, box beam, etc.) Steel Concrete Steel Concrete CIP Concrete Slab Span Prestressed concrete I-Beam Pier foundation type (spread footings, driven piles, drilled shafts, etc.) Driven Piles Drilled Shafts Drilled Shafts Driven Piles Spread footing Pier footing on Piles Approach height 23 27 23 23 20 Geotechnical report available? Yes Yes No Yes No Yes Were repairs performed? Yes Yes Yes Yes Yes No Any instrumentation data available? No No No No No Yes Route No./Structure No. I-135 US 75 I-35 US 50 I-40 15725 6015 Crossing (over/under) Broadway and 1st St. Over 46th St. Under 87th St. Over Mary St. SH-9A Over Johnson Creek and Lower Arnot Rd. Type of spans (simple, continuous, cantilever, etc.) Continuous Continuous Continuous Continuous Continuous Continuous Type of abutments (integral, spill- through, full height, perched, stub, etc.) Integral Integral Integral Integral Stub Stub Approach fill or wall type (Fill with side slope, MSE wall, etc.) MSE Wall MSE Wall MSE Wall MSE Wall Fill w/ side slope Fill w/ side slope As-built drawings available? No No No No No Yes Boring logs available? Yes Yes No Yes Yes Yes Maintenance records available? No No No No Yes Yes Any photos of bridge damage and/or repairs available? Probably ??? No No Yes Yes (continued on next page)

301 Table B.1. Bridge Characteristics, Geological Information, and Movements Question 3: Construction Sequence Substructure, Approach Fill/ Wall, Superstructure Substructure, Approach Fill/ Wall, Superstructure Substructure, Approach Fill/ Wall, Superstructure Substructure, Approach Fill/ Wall, Superstructure Approach Fill/ Wall, Sub- structure, Superstructure Question 4: Geological Info Alluvial and residual clay overlying sand or shale bedrock Glacial drift and alluvial soils over glacial till followed by Pennsylvanian bedrock Residual clay soil over Pennsylvanian bedrock Loessial soil and fill above allu- vial sand Stiff to hard sandy clay (Liquid Limit (LL) ~50, Plas- ticity Index (PI)~30, #200 75%) Silt with gravel and cobbles overlying non-plastic silt and silty sand and gravel Question 5: Bridge Movements Vertical Movement NA NA NA NA 12″ at abutment 1-4″ prior to construction Horizontal Movement NA NA NA NA NA NA Note: NA = not available. (continued) Table B.2. Effects of Movement on Structure Question 6: Effects of Movement on Structure Indicate if distress types were tolerable or not based on the following definition: “Movement is NOT tolerable if damage requires costly maintenance and/or repairs AND a more expensive construction to avoid this would have been preferable.” State A Damage to abutments: NO Damage to piers: NO Vertical Displacement: NO Horizontal Displacement: NO Distress in superstructure: NO Damage to railings, curbs, sidewalks or parapets: NO Damage to bearings: NO Poor riding quality: YES Not given or corrected: NA None: YES Other: YES State A Damage to abutments: Tolerable until it effects bearings or severe deterioration of rebar Damage to piers: same as abutments Vertical Displacement: not much of a problem, typically caused by deterioration of beam end, fixed by jacking beam and repairing section loss Horizontal Displacement: not much of a problem, let it go until it gets excessive Distress in superstructure: not tolerated if cracks in steel beam or shear cracks in concrete beam. Joint normally tolerated unless pushing bents or abutments and causing damage Damage to railings, curbs, sidewalks or parapets: tolerated Damage to bearings: not tolerated-repair by replacing bearings with elastomeric pads or resetting rocker bearings Poor riding quality: generally tolerated, mud-jack approach slabs if excessive Not given or corrected: NA None: NA Other: NA (continued on next page)

302 Table B.2. Effects of Movement on Structure State B Damage to abutments: NO, settlement resulted in end span cantilevered from pier, loss of bearing Damage to piers: Vertical Displacement: NO, shims added, caused crack to form over pier Horizontal Displacement: Distress in superstructure: NO, crack/hinge over pier Damage to railings, curbs, sidewalks or parapets: NO, cracks in parapet Damage to bearings: NO Poor riding quality: NO Not given or corrected: NA None: NA Other: After hinge/crack in slab span, end span acted as simply supported. End span was not designed or reinforced to act as a simple span State C Damage to abutments: Not tolerable, except for slope protection and minor separation of wing wall from the abutment Damage to Piers: Not tolerable, tolerable if crack widths are less than 0.025″ based on Oregon DOT cracking guidelines Vertical Displacement: tolerable Horizontal Displacement: assumed tolerable Distress in superstructure: not tolerable, tolerable if crack width is less than 0.025″ based on Oregon DOT crack guidelines Damage to railings, curbs, sidewalks, or parapets: tolerable Damage to bearings: tolerable Poor Riding quality: tolerable Not given or corrected during construction: potential settlement was addressed in construction None: NA Other: NA Note: NA = not available. (continued) for the end span. This resulted in the end span becoming a sim- ple span which was not considered in the design. The move- ment was a result of drilled shafts for the abutments being founded in fill instead of bedrock. The fourth response indicated that damage to railings, curbs, sidewalks, parapets, and bearings are tolerable. Cracking of piers and superstructure components are tolerable up to a certain limit based upon guidelines used by the Oregon DOT. Ten agencies responded to two questions about criteria for movements permitted on new bridges. Their responses are below. Question 1: does your agency follow the criteria of article C10.5.5.2 of aaSHTo (2007)? Responses are: • Yes, we use the criteria of Article C10.5.5.2 of the AASHTO LRFD Specification (2) • No, we do not use the criteria of Article C10.5.5.2 of the AASHTO LRFD Specification (8) • No response (6) Those agencies that do not follow the criteria of Article C10.5.5.2 of the AASHTO LRFD Specification were asked to provide the deflection limits that they use. These limits are provided in Table B.3. Question 2: does the agency have criteria for permissible horizontal movement (in longitudinal direction of the bridge)? The responses to the above question are: • Yes (3) • No (7) • No response (6) The allowable horizontal movement limits are shown in the table on the following page Agency D limits horizontal move- ment to that which can be accommodated by the bearings and joints within the structure while others provide a finite value. Limits provided by various agencies which do not follow Article C10.5.5.2 of AASHTO are shown in Table B.3.

303 Table B.3. Allowable Vertical and Horizontal Movements Movement Agency A Agency B Agency C Agency D Agency E Agency F Agency G Total Vertical Movement Axial Elastic Only 1″ Assessed on a case by case basis, and if likely to continue steps are taken to stop settlement. 1″ 1″ Follows local/ state requirements 1.5″ Differential Vertical Movement 0″ 1″ Case by case 1″ Structure Specific Angular Distortion 0″ 0.1% of Span Length 0.0025 for simple span 0.0015 for continuous span Structure Specific Horizontal Movement <2″ due to thermal loading for inte- gral abutments founded on a single row of piles 0″ Case by case, thermal, shrinkage, and live load movement must be less than that allowed by bearings and expansion joints Not specified in design, is specified for construction 1″